Method and apparatus for holding a mold assembly and molding an optical lens using the same

ABSTRACT

An apparatus and method for holding a mold assembly and molding an optical lens using the same. In one aspect, the present invention provides an apparatus for holding a mold assembly, wherein the mold assembly includes a front mold, a back mold and a strip wrapping around the edges of the front mold and back mold to form a sleeve. In one embodiment, the apparatus includes a first portion and a second portion. The first portion has a top part, a bottom part, and a middle part connecting the top part and the bottom part, the middle part including a base and a holder coupled to the base. The second portion has a top part, a bottom part, and a middle part connecting the top part and the bottom part, the middle part including a base and a holder coupled to the base. The first portion and the second portion are pivotally coupled together at the bottom parts so that the top part of the first portion and the top part of the second portion can be closed to define a housing for receiving the mold assembly therein, wherein the top part of the first portion and the top part of the second portion can also be opened for receiving the mold assembly in the housing.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to an apparatus and method forholding a mold assembly and molding an optical lens using the same. Inparticular, the present invention relates to an apparatus and method ofholding a mold assembly to mold an optical lens, wherein the moldassembly includes a front mold, a back mold and a strip wrapping aroundthe edges of the front mold and the back mold to form a sleeve.Moreover, the present invention discloses an apparatus and method forholding an optical device such as a mold so that the optical surface ofthe mold is protected.

[0003] 2. Background

[0004] Most lenses today are made by molding plastic because of itslight weight, density, refractive index, and impact resistance. To forma lens, two molds, often referred to as a front mold and a back mold inthe art of lens making, are used. Each mold has a facing inside surfaceor an optical surface. When these two molds are properly positioned at adesired distance and rotational orientation to each other, their facinginside surfaces are a negative image of the surfaces of the lens to beformed. A closure member is used to necessarily seal the cavity. Then afluid lens-forming material, normally a liquid monomer, is placed andcontained in the cavity defined by the two molds and the closure member.Once the fluid lens-forming material is in the cavity, it is cured toform a hardened polymeric lens taking the shape of the molds.

[0005] Two kinds of closure members are now used in making the lenses.The first kind of closure member is a gasket, which has been used widelyin the art. Currently available gaskets are known as T-gaskets.Different T-gaskets are required to form varying power lenses becauseeach T-gasket sets a predetermined axial separation between molds. Thus,in order to meet the requirements of various possible types and powersof lenses, a portfolio of different T-gaskets over a wide range ofdifferent geometrical characteristics is needed. Not only is it costlyto create and keep such a portfolio, but even with a portfolio it issometimes still impossible to meet a customer's need in a timely mannerbecause the customer may require a lens with power or type outside theportfolio, and then a customer-tailored T-gasket has to be made.

[0006] A second kind of closure member has been proposed as analternative. Namely, a closure member can be made by wrapping a striparound the edges of the molds and thus a molding cavity can be createdon demand in situ at the last minute by the molds and the strip. Anumber of references discloses various ways to achieve this goal. Onegroup of references discloses lens casting using two molds joinedtogether using a strip by gluing or using adhesive tape to attach thestrip to the molds to form a molding cavity. U.S. Pat. No. 5,213,825issued to Shimizu et al., U.S. Pat. No. 4,497,754 issued to Padoan, U.S.Pat. No. 3,211,811 issued to Lanman, and U.S. Pat. Nos. 5,547,618 and5,662,839 issued to Magne are some examples in this category. Onedrawback related to this approach is that traces of adhesives may remainon the molds and on the finished lens and, hence, a specific cleaningprocedure must be utilized to clean up the adhesives. Moreover, becausethe molds are held firmly by adhesives once the molds are assembled andthe molding cavity is formed, the molds cannot move relative to thetape, or within the tape during the lens casting process.

[0007] Attempting to avoid the drawbacks caused by adhesives, anothergroup of references disclose lens casting simply using a strip of heatshrinkable synthetic material or similar deformable material tocooperate with the molds to form a molding cavity. For examples, U.S.Pat. No. 2,406,361 issued to Fairbank et al. and U.S. Pat. No. 5,611,969issued to Cano et al. both disclose just using such tape to form thecavity into which monomer is injected. While this approach may havesucceeded in avoiding the drawbacks caused by adhesives, it also doesnot allow the molds to move relative to the tape or within the tape oncethe molds are assembled and the molding cavity is formed. Therefore, tocompensate any shrinkage of the lens forming material during the lenscasting process, the tape used in these references must crumple orwrinkle. However, because the tape may not be crumpled or wrinkleduniformly under the pressure of the molds during the lens polymerizationprocess, it may negatively impact the quality of the lens to be molded.Moreover, because the tape is heated to shrink it onto the moldstightly, separating the tape from the molds once the lens is maderequires special care and extra effort, which increases labor cost andimpedes automation of the molding process. Furthermore, all citedreferences which disclose using the tape arrangement do not have theflexibility to adjust the relative axial position of the molds once themolds are closed with the tape. If a mistake is made in setting up anappropriate axial positions of the molds, the tape has to be unwrappedand the whole process has to start over again.

[0008] In order to overcome these and other disadvantages, a new type ofstrip is disclosed in U.S. Pat. No. 6,099,764 issued to Su et al., whichis incorporated herein by reference for background information only. Asdisclosed, the strip has a first and an opposed second end, an interiorsurface and an opposed outer surface, and a recess channel formed on theinside surface extending from the first end to the second end. A fluidlens-forming material can be introduced into a molding cavity throughthe recess channel by a filling needle. However, the recess channel isformed on the inside surface, and there is no indication on the outersurface as to where the recess channel is located. Thus, one concern isthat it may be difficult for a user to properly position the fillingneedle into the recess channel. The second concern is that portions ofthe strip at the recess channel are thinner than other parts of thestrip, which may affect the strength of the strip. Therefore, there isstill a need in the art for new or improved molding method andapparatus.

[0009] Additionally, during the molding process, often it needs totransport an optical device such as a mold from one place to anotherplace, or to position the mold at a desired location or position. Indoing so, one must be careful not to touch the optical surface of themold to keep the optical surface of the mold clean so that the qualityof optical lenses to be molded from the mold is not compromised. Thus,there is also a need in the art for new or improved apparatus forholding the optical device.

SUMMARY OF THE INVENTION

[0010] The present invention overcomes the disadvantages of the priorart and provides several related methods and devices for holding a moldassembly and molding an optical lens using the same. In one aspect, thepresent invention relates to a method for molding an optical lens usinga front mold and a back mold with facing inside surfaces that are anegative image of the surfaces of the optical lens and that are at aproper distance and rotational orientation to each other, wherein eachof the front mold and back mold has an edge. In one embodiment, themethod includes the step of wrapping a strip around the edges of thefront mold and the back mold to form a sleeve. The strip has a bodyportion that has a first end and an opposed second end, an interiorsurface and an opposed outer surface, and a first flange and a secondflange, and a partially encircled portion defining an elongated channelextending from the first end to the second end, wherein the partiallyencircled portion is located between the first flange and the secondflange and protruding away from the outer surface of the body portion,and the inside surface of the body portion defines an opening thereinbetween the first flange and the second flange in fluid communicationwith the elongated channel. As formed, the sleeve has a longitudinalaxis and a diameter, and cooperates with the front mold and the backmold to define a molding cavity, wherein the molding cavity is in fluidcommunication with the elongated channel through the opening. Moreover,the method includes the steps of injecting a fluid lens-forming materialinto the molding cavity through the elongated channel, and curing thefluid lens-forming material to form the optical lens.

[0011] In one embodiment, the strip may be made from a nonadhesiveplastic film, wherein the nonadhesive plastic film includes anelastomeric material selected from the group of polyurethane, polyvinylchloride, organosilicon elastomer and thermoplastic rubbers containing astyrene-ethylene-propylene (butylene) block copolymer. The thickness ofthe non-adhesive plastic film is between 1.0 millimeter and 8.0millimeter.

[0012] The method further includes the steps of securing together inface-to-face engagement of the interior surfaces of the first and secondends of the strip to form the sleeve to close the molding cavity and toform a tail, using the tail as a handler to handle the molds, and usinga port, which is formed by the portion of the elongated channel at thefirst end and the portion of the elongated channel at the second endafter the first end and the second end of the strip are secured togetherin the face-to-face engagement of the interior surface of the first andsecond ends of the strip, as a venting channel and a passage forestablishing a fluid communication to the molding cavity.

[0013] In yet another embodiment, the method further includes the stepof placing a plug in a direction substantially parallel to thelongitudinal axis of the sleeve, across the edges of the front mold andthe back mold and between the first end and the second end of the stripbefore the first end and the second end are secured together to closethe molding cavity. The plug can be made from a nonadhesive plasticmaterial that has an elastomeric material selected from the group ofpolyurethane, polyvinyl chloride, organosilicon elastomer andthermoplastic rubbers containing a styrene-ethylene-propylene (butylene)block copolymer. Moreover, the plug cross-sectionally is triangular.Alternatively, the plug cross-sectionally can take other geometricshapes such as square, oval, circle, etc.

[0014] In another aspect, the present invention provides a strip formolding an optical lens. In one embodiment, the strip has a body portionthat has a first end and an opposed second end, an interior surface andan opposed outer surface, and a first flange and a second flange, and apartially encircled portion defining an elongated channel extending fromthe first end to the second end. The partially encircled portion islocated between the first flange and the second flange and protrudingaway from the outer surface of the body portion and the inside surfaceof the body portion defines an opening therein between the first flangeand the second flange in fluid communication with the elongated channel.

[0015] In yet another aspect, the present invention provides anapparatus for holding a mold assembly, wherein the mold assemblyincludes a front mold, a back mold and a strip wrapping around the edgesof the front mold and back mold to form a sleeve. The strip has a bodyportion that has a first end and an opposed second end, an interiorsurface and an opposed outer surface, and an elongated channel extendingfrom the first end to the second end. As formed, the sleeve has alongitudinal axis and a diameter and cooperating with the front mold andthe back mold to define a molding cavity, wherein the molding cavity isin fluid communication with the elongated channel.

[0016] In one embodiment, the apparatus includes a first portion and asecond portion. The first portion has a top part that has a top surface,an opposite bottom surface, a bore defined therein extending between thetop surface and the bottom surface, a bottom part, and a middle partconnecting the top part and the bottom part, wherein the middle partincludes a base and a holder coupled to the base. The second portion hasa top part that has a top surface, an opposite bottom surface, a boredefined therein extending between the top surface and the bottomsurface, a bottom part, and a middle part connecting the top part andthe bottom part, wherein the middle part includes a base and a holdercoupled to the base. The first portion and the second portion arepivotally coupled together at the bottom parts so that the top part ofthe first portion and the top part of the right portion can be closed todefine a housing for receiving the mold assembly therein, wherein thetop part of the first portion and the top part of the second portion canalso be opened for receiving the mold assembly in the housing.

[0017] Moreover, in one embodiment, the holder of the first portion hasa body portion that has a top surface, an opposite bottom surface, arear surface, an opposite front surface, a first side surface and anopposite second side surface, a first arm adjacent the body portion tothe first side surface of the body portion, wherein the first armextends away from the body portion and has a first surface curved forpartially receiving the mold assembly, and a second arm adjacent thebody portion to the second side surface of the body portion, wherein thesecond arm extends away from the body portion and has a first surfacecurved for partially receiving the mold assembly. The first arm andsecond arm are located opposite to each other across the body portionand define a recess with the body portion. Additionally, the first arm,the second arm and the body portion of the first portion define anopening adjacent to the top surface, wherein the opening is incommunication with the bore of the top part of the first portion and therecess of the holder of the first portion.

[0018] Likewise, the holder of the second portion has a body portionthat has a top surface, an opposite bottom surface, a rear surface, anopposite front surface, a first side surface and an opposite second sidesurface, a first arm adjacent the body portion to the first side surfaceof the body portion, wherein the first arm extends away from the bodyportion and has a first surface curved for partially receiving the moldassembly, and a second arm adjacent the body portion to the second sidesurface of the body portion, wherein the second arm extends away fromthe body portion and has a first surface curved for partially receivingthe mold assembly. The first arm and second arm are located opposite toeach other across the body portion and define a recess with the bodyportion. Additionally, the first arm, the second arm and the bodyportion of the second portion further define an opening adjacent to thetop surface, wherein the opening is in communication with the bore ofthe top part of the second portion and the recess of the holder of thesecond portion.

[0019] In yet another aspect, the present invention provides anapparatus for holding a mold, wherein the mold has an optical surfaceand a second surface opposite the optical surface and is characterizedby a radius R_(m). In one embodiment, the apparatus includes a firstring defining an opening. The first ring has a ring body that has alongitudinal axis, a first surface and an opposite second surface, andan outer surface and an interior surface, wherein the outer surface ischaracterized by a first radius, R₁, and the interior surface ischaracterized by a second radius, R₂, and a plurality of teeth formed onthe first surface in a circle and protruding away from the ring bodyalong the longitudinal axis, wherein the circle has a radius, R_(c),complementary to the radius of the mold R_(m) to allow the plurality ofteeth to receive and hold the mold.

[0020] Moreover, the apparatus includes a second ring that has a base,having a first surface and an opposite second surface, a ring bodyformed on the first surface of the base, the ring body having alongitudinal axis, a top surface, an outer surface and an interiorsurface, wherein the outer surface is characterized by a first radius,R′₁, and the interior surface is characterized by a second radius, R′₂,and a plurality of teeth formed on the top surface in a circle andprotruding away from the ring body along the longitudinal axis, whereinthe circle has a radius, R′_(c), complementary to the radius of the moldR_(m) to allow the plurality of teeth to receive and hold the mold.

[0021] In a further aspect, the present invention provides a method forholding an optical device such as a mold, wherein the optical device hasan optical surface and a second surface opposite the optical surface andis characterized by a radius R_(m). In one embodiment, the methodincludes the steps of providing a first ring that has a longitudinalaxis and a plurality of teeth formed in a circle, wherein the circle hasa radius, R_(c), complementary to the radius of the optical device,R_(m), and picking up the optical device with the plurality of teethtowards the second surface of the optical device to receive and hold theoptical device so that the optical surface of the optical device isfacing away from the first ring. The method further includes the stepsof providing a second ring that has a longitudinal axis and a pluralityof teeth formed in a circle, wherein the circle has a radius, R′_(c),complementary to the radius of the mold, R_(m), directing the opticaldevice so that the optical surface of the optical device is facing thesecond ring, and the first ring and the second ring are co-axial,pushing the first ring towards the second ring so that the second ringreceives and holds the optical device with the optical surface of theoptical device facing towards to the second ring, and removing the firstring from the optical device. The method further includes the step ofrotating the second ring in a relative motion so as to position theoptical device at a desired orientation. The optical device can be anoptical lens having at least one optical surface, or a mold that can beused to produce an optical lens.

[0022] In yet another aspect, the present invention provides anapparatus for holding a mold, wherein the mold has an optical surfaceand a second surface opposite the optical surface and is characterizedby a radius R_(m). In one embodiment, the apparatus has a first ringthat has a longitudinal axis and a plurality of teeth formed in acircle, wherein the circle has a radius, R_(c), complementary to theradius of the optical device R_(m), means for picking up the opticaldevice so that the optical surface of the optical device is facing awayfrom the first ring, a second ring that has a longitudinal axis and aplurality of teeth formed in a circle, wherein the circle has a radius,R′_(c), complementary to the radius of the optical device R_(m), meansfor directing the optical device so that the optical surface of theoptical device facing the second ring and the first ring and the secondring are co-axial, means for pushing the first ring towards the secondring so that the second ring receives and holds the optical device withthe optical surface of the optical device facing towards to the secondring, and means for removing the first ring from the optical device. Theapparatus further includes means for rotating the second ring in arelative motion so as to position the optical device at a desiredorientation. Likewise, the optical device can be an optical lens havingat least one optical surface, or a mold that can be used to produce anoptical lens.

[0023] These and other aspects will become apparent from the followingdescription of the various embodiments taken in conjunction with thefollowing drawings, although variations and modifications may beeffected without departing from the spirit and scope of the novelconcepts of the disclosure.

BRIEF DESCRIPTION OF THE FIGURES OF THE DRAWINGS

[0024]FIG. 1 is a perspective view of a holding device according to thepresent invention.

[0025]FIG. 1A is a perspective view of a strip for forming a moldassembly according to one embodiment of the present invention.

[0026]FIG. 1B is a cross-sectional view of the strip of FIG. 1A.

[0027]FIG. 2 is a vertical cross-sectional view of part of the holdingdevice as shown in FIG. 1.

[0028]FIG. 2A is a perspective view of a holder that can be utilized inthe holding device of FIG. 1 according to one embodiment of the presentinvention.

[0029]FIG. 2B is a side view of the holder as shown in FIG. 2A.

[0030]FIG. 2C a top view of the holder as shown in FIG. 2A.

[0031]FIG. 3 is a cross-sectional view of the holding device as shown inFIG. 2.

[0032]FIG. 4 is a top view of the holding device as shown in FIG. 3.

[0033]FIG. 5 is a bottom view of the holding device as shown in FIG. 3.

[0034]FIG. 6 schematically shows that the holding device of FIG. 1 is inan opened position to receive a molding assembly according to oneembodiment of the present invention.

[0035]FIG. 7 is a perspective view of an apparatus for holding a moldaccording to one embodiment of the present invention.

[0036]FIG. 8 is a side view of the holding apparatus as shown in FIG. 7.

[0037]FIG. 9 is a top view of a second ring of the holding apparatus asshown in FIG. 8.

[0038]FIG. 10 is a top view of a first ring of the holding apparatus asshown in FIG. 8.

DETAILED DESCRIPTION OF THE INVENTION

[0039] The present invention is more particularly described in thefollowing examples that are intended as illustrative only since numerousmodifications and variations therein will be apparent to those skilledin the art. As used in the specification and in the claims, “a” can meanone or more, depending upon the context in which it is used. Severalembodiments are now described with reference to the figures, in whichlike numbers indicate like parts throughout the figures. Subtitles, ifany, are provided for helping a reader to understand various embodimentsand are not intended to limit upon the scope of the invention.

[0040] Referring first generally to FIGS. 1-6, in one aspect, thepresent invention relates to a method for molding an optical lens. Inone embodiment, the method is practiced by using a front mold 12 and aback mold 14 whose facing inside surfaces are a negative image of thesurfaces of the optical lens 10 at a proper distance and rotationalorientation to each other. The front mold 12 and back mold 14 each hasan edge 13, 15, respectively.

[0041] The method is also practiced by a strip 20 that has a bodyportion 22 that has a first end 24 and an opposed second end 26, aninterior surface 28 and an opposed outer surface 30, and a first flange32 and a second flange 34, and a partially encircled portion 36 definingan elongated channel 38 extending from the first end 24 to the secondend 26. The partially encircled portion 36 is located between the firstflange 32 and the second flange 34. The partially encircled portion 36is protruding away from the outer surface 30 of the body portion 22.Additionally, the partially encircled portion 36 has an opening 40formed on the interior surface 28 of the body portion 22 between thefirst flange 32 and the second flange 34 in fluid communication with theelongated channel 38.

[0042] In one embodiment, the strip 20 can be wrapped around the edges13, 15 of the front mold 12 and back mold 14 with the strip 20 to form asleeve 50. In doing so, the strip 20 can be wrapped around the edges 13,15 of the front mold 12 and back mold 14 such that the interior surface28 of the strip 20 is in direct contact with the edges 13, 15 of thefront mold 12 and back mold 14. The formed sleeve 50 has a longitudinalaxis A, and a diameter and cooperates with the front mold 12 and theback mold 14 to define a molding cavity 16. The molding cavity 16 is influid communication with the elongated channel 38 through the opening40. The front mold 12 and back mold 14 and the sleeve 50 form alens-forming assembly or mold assembly 11. A fluid lens-forming materialcan be injected into the molding cavity 16 through the elongated channel38 and can then be cured to form the optical lens 10.

[0043] One aspect of the sleeve 20 of the present invention is thesleeve material. In one embodiment, a desirable characteristic is thatthe sleeve material is nonadhesive at least at where the interiorsurface 28 is formed, so that it does not entirely prohibit the axialmovement of the molds 12, 14. Moreover, the sleeve material isrelatively soft, so that it can be wrapped around against the edges ofthe molds 12, 14 to form the sleeve 50. Furthermore, the sleeve materialis elastomeric, so that once the sleeve 50 is formed and the front mold12 and back mold 14 are contained within the sleeve 50, the tension ofthe elastomeric material forces the sleeve 50 tightly against the edgesof the molds 12, 14 along the radial axis. Still another aspect of thesleeve material is that it is chemically compatible with thelens-forming fluid to avoid inhibiting polymerization of the fluid.Another aspect of the sleeve material is that it is relatively thick sothat it can sustain the tension force.

[0044] As shown in FIG. 1A, the strip 20 has a thickness H between theinterior and outer surfaces 28 and 30. The range of thickness H is from1 millimeter to 8 millimeter, preferably 2 millimeter to 6 millimeterand optimally 3 millimeter to 4 millimeter. Note that the thickness ofthe encircled portion 36 is not significantly thinner than that of theother parts of the strip 20. Indeed, in one embodiment as shown in FIG.1A, they are substantially the same so that the strength of the strip 20is substantially uniform.

[0045] In one embodiment, a suitable sleeve material is thermoplasticrubber that contains KRATON®G, a styrene-ethylene-propylene (butylene)block copolymer, sold by Shell Oil Company® of Houston, Tex. Such rubberincludes those sold under the trade names DYNAFLEX®G2703, 2711, and 2712by GLS Corporation of Cary, Illinois. These rubbers have a Shore Ahardness ranging from about 43 to 62, a specific gravity of about 0.9g/cc, a tensile modulus at 300% elongation ranging from about 355 to470, tensile strength at break of about 680 to 1000 psi, and a tearstrength of about 113 to 127. These rubbers have smooth surfaces andhave a thickness in a range of 1 mm-8 mm. The sleeve material of thepresent invention, however, is not limited to a single material. Infact, the desired sleeve material can be dependent on the specificmonomer compound used to form the lens. That is, a certain sleevematerial may be utilized with a particular lens-forming fluid anddifferent type of sleeve material with another lens material. Among manyavailable materials, it is found that the present invention can besatisfactorily practiced with polyurethane, polyvinyl chloride,organosilicon elastomer as well as KRATON®G and thermoplastic rubberscontaining a styrene-ethylene-propylene (butylene) block copolymer.

[0046] The first and second ends 24, 26 of the strip 20 can be securedtogether in face-to-face engagement of the interior surfaces of thefirst end 24 and the second end 26 to close the molding cavity 16 andform a tail 41. The tail 41 may function as a handler to handle themolds 12, 14. Additionally, a port 42 is formed by the portion of theelongated channel 38 at the first end 24 and the portion of theelongated channel 38 at the second end 26 after the first end 24 and thesecond end 26 of the strip 20 are fastened together. The port 42 can beused as a venting channel and a passage for establishing a fluidcommunication to the molding cavity 16.

[0047] In yet another embodiment, a plug 44 can be placed in a directionsubstantially parallel to the longitudinal axis A, across the edges 13,15 of the front mold 12 and the back mold 14 and between the first end24 and the second end 26 of the strip 20 before the first end 24 and thesecond end 26 of the strip 20 are fastened together to close the moldingcavity 16. The plug 44 can be made from a nonadhesive plastic material.The nonadhesive plastic material includes an elastomeric materialselected from the group of polyurethane, polyvinyl chloride,organosilicon elastomer and thermoplastic rubbers containing astyrene-ethylene-propylene (butylene) block copolymer. Alternatively,the plug 44 can be made form metal, alloy, ceramic material, plasticmaterial, glass, or the like. Cross-sectionally, the plug 44 can takevarious geometric shapes such as round, oval, triangular, rectangular,square, etc. In the embodiment as shown in FIGS. 1 and 2, the plug 44 istriangular.

[0048] By utilizing the plug 44 in the manner as described above, anyunfilled spaces created between the interior surfaces of the strip 20and the edges of the edges 13, 15 of the front mold 12 and the back mold14 when the first end 24 and the second end 26 of the strip 20 arefastened together to close the molding cavity 16 can be substantiallyfilled by the plug 44, which not only substantially blocks potentialspill-over of the fluid lens-forming material from the molding cavity 16but as a cushion allows the strip 20 to tightly wrap around the edges13, 15 of the front mold 12 and the back mold 14. Alternatively, thepresent invention can also be practiced without the plug 44.

[0049] As formed, the mold assembly 11 can be processed at an assemblystation such as one disclosed in U.S. Pat. No. 6,099,764, which isincorporated herein by reference for background information only. Otherassembly devices can be used to process the lens forming assembly. Inparticular, simple and inexpensive holding devices that can hold andprocess the mold assembly 11 are needed for on site lens making.

[0050] In one aspect, the present invention provides such an apparatusor holding device 100 for holding the mold assembly 100. In oneembodiment, the holding device 100 includes a first portion 102 and asecond portion 152. The first portion 102 includes a top part 104 thathas a top surface 110, an opposite bottom surface 112, a bore 114defined therein extending between the top surface 110 and the bottomsurface 112. The first portion 102 further includes a bottom part 108,and a middle part 106 connecting the top part 104 and the bottom part108. The middle part 106 includes a base 116 and a holder 118 coupled tothe base 116. The second portion 152 includes a top part 154 that has atop surface 160, an opposite bottom surface 162, a bore 164 definedtherein extending between the top surface 160 and the bottom surface162. The second portion 152 further includes a bottom part 158, and amiddle part 156 connecting the top part 154 and the bottom part 158. Themiddle part 156 includes a base 166 and a holder 168 coupled to the base166. The first portion 102 and the second portion 152 are pivotallycoupled together at the bottom parts 108, 158 so that the top part 104of the first portion 102 and the top part 154 of the second portion 152can be closed to define a housing 120 for receiving the mold assembly 11therein. The top part 104 of the first portion 102 and the top part 154of the second portion 152 can also be opened for receiving in orremoving away the mold assembly 11 from the housing 120, respectively.

[0051] Moreover, in one embodiment as shown in FIGS. 2A-2C, the holder118 of the first portion 102 has a body portion 122. The body portion122 has a top surface 124, 30 an opposite bottom surface 126, a rearsurface 128, an opposite front surface 130, and a first side surface 132and an opposite second side surface 134. The holder 118 further has afirst arm 136 and a second arm 140. The first arm 136 is adjacent to thefirst side surface 132 of the body portion 122, extends away from thebody portion 122 and has a first surface 138 curved for partiallyreceiving the mold assembly 11. The second arm 140 is adjacent to thesecond side surface 134 of the body portion 122, extends away from thebody portion 122 and has a first surface 142 curved for partiallyreceiving the mold assembly 11. The first arm 136 and second arm 140 arelocated opposite to each other across the body portion 122 and define arecess 144 in cooperation with the body portion 122.

[0052] Furthermore, the first arm 136, the second arm 140 and the bodyportion 122 in cooperation define an opening 146 adjacent to the topsurface 124. The opening 146 is in communication with the bore 114 ofthe top part 104 of the first portion 102 and the recess 144 of theholder 118 of the first portion 102. The body portion 122 additionallyhas an edge 147 that is formed on the front surface 130, at which theopening 146 and the recess 144 merge. The first arm 136 has a secondsurface 139 curved for partially receiving the mold assembly 11. Thefirst curved surface 138 and the second curved surface 139 havesubstantially same curvature complementary to the edges 13, 15 of thefront mold 12 and the back mold 14. As best shown in FIG. 2A, the firstcurved surface 138 and the second curved surface 139 are located apartfrom each other thereby defining a recess 137 therebetween. The base 116of the middle part 106 has a groove 117, as shown in FIG. 3, which issized to complementarily receive part of the body portion 122 of theholder 118 therein.

[0053] Referring to FIGS. 1, 3 and 4, the body portion 122 has a pinchhole 149 extending from the first side surface 132 to the second sidesurface 134. Additionally, the base 116 of the middle part 106 has apinch hole 119 complementary, position wise and size wise, to the pinchhole 149 of the body portion 122 of the holder 118. Moreover, the middlepart 106 has a pinch 148 placed in both the pinch hole 149 of the bodyportion 122 of the holder 118 and the pinch hole 119 of the base 116 soas to couple the base 116 and the holder 118 together and allow theholder 118 to be partially received in the groove 117 of the base 116.As such coupled, the holder 118 is slightly rotatable about the pinch148 therein. Optionally, an elastic member 148 a such as a spring can beutilized to facilitate the coupling of the base 116 and the holder 118.In one embodiment, the elastic member 148 a is received in a recess 117a in the groove 117 of the base 116 and a complementary recess 128 a inthe rear surface 128 of the body portion 122.

[0054] Additionally, the holder 168 of the second portion 152 issubstantially identical to the holder 118 of the first portion 102 interm of the structure. That is, the holder 168 has a body portion 172.The body portion 172 has a top surface 174, an opposite bottom surface176, a rear surface 178, an opposite front surface 180, and a first sidesurface 182 and an opposite second side surface 184. The holder 168further has a first arm 186 and a second arm 190. The first arm 186 isadjacent to the first side surface 182 of the body portion 172, extendsaway from the body portion 172 and has a first surface 188 curved forpartially receiving the mold assembly 11. The second arm 190 is adjacentto the second side surface 184 of the body portion 172, extends awayfrom the body portion 172 and has a first surface 192 curved forpartially receiving the mold assembly 11. The first arm 186 and secondarm 190 are located opposite to each other across the body portion 172and define a recess 194 in cooperation with the body portion 172.

[0055] Furthermore, the first arm 186, the second arm 190 and the bodyportion 172 in cooperation define an opening 196 adjacent to the topsurface 174. The opening 196 is in communication with the bore 164 ofthe top part 154 of the first portion 152 and the recess 194 of theholder 168 of the first portion 152. The body portion 172 additionallyhas an edge 197 that is formed on the front surface 180, at which theopening 196 and the recess 194 merge. The first arm 186 has a secondsurface 189 curved for partially receiving the mold assembly 11. Thefirst curved surface 188 and the second curved surface 189 havesubstantially same curvature complementary to the edges 13, 15 of thefront mold 12 and the back mold 14. As best shown in FIG. 1, the firstcurved surface 188 and the second curved surface 189 are located apartfrom each other thereby defining a recess 187 therebetween. The base 166of the middle part 156 has a groove 167, as shown in FIG. 3, which issized to complementarily receive part of the body portion 172 of theholder 168 therein.

[0056] Referring to FIGS. 1, 3 and 4, the body portion 172 has a pinchhole 199 extending from the first side surface 182 to the second sidesurface 184. Additionally, the base 166 of the middle part 156 has apinch hole 169 complementary, position wise and size wise, to the pinchhole 199 of the body portion 172 of the holder 168. Moreover, the middlepart 156 has a pinch 198 placed in both the pinch hole 199 of the bodyportion 172 of the holder 168 and the pinch hole 169 of the base 166 soas to couple the base 166 and the holder 168 together and allow theholder 168 to be partially received in the groove 167 of the base 166.As such coupled, the holder 168 is slightly rotatable about the pinch198 therein. Optionally, an elastic member 198 a such as a spring can beutilized to facilitate the coupling of the base 166 and the holder 168.In one embodiment, the elastic member 198 a is received in a recess 167a in the groove 167 of the base 166 and a complementary recess 178 a inthe rear surface 178 of the body portion 172.

[0057] Referring now to FIGS. 1 and 4, the top part 104 of the firstportion 102 has a first side surface 202, an opposite second sidesurface 204, and a contact side surface 206 connecting the first sidesurface 202 and the second side surface 204. A groove 208 is formed onthe contact side surface 206. Projections 210, 212 are extending fromthe contact side surface 206 away from the bottom surface 112 of the toppart 104. Likewise, the top part 154 of the second portion 152 has afirst side surface 222, an opposite second side surface 224, and acontact side surface 226 connecting the first side surface 222 and thesecond side surface 224. A groove 228 is formed on the contact sidesurface 226, which is complementary, position wise and size wise, to thegroove 208 formed on the contact side surface 206 of the first portion102. Projections 230, 232 are extending from the contact side surface226 away from the bottom surface 162 of the top part 154. Projections230, 232 are complementary, position wise and size wise, to theprojections 210, 212 of the first portion 102, respectively, so thatwhen the top part 104 of the first portion 102 and the top part 154 ofthe second portion 152 are closed to define the housing 120 forreceiving the mold assembly 11 therein, the projection 210 (or theprojection 212 or both) formed on the contact side surface 202 of thefirst portion 102 and the projection 230 (or the projection 232 or both)formed on the contact side surface 226 of the second portion 152 contacteach other, respectively, and the groove 208 formed on the contact sidesurface 206 of the first portion 102 and the groove 228 formed on thecontact side surface 226 of the second portion 152 form an opening 240.The opening 240 is sized such as to allow the tail 41 of the moldingassembly 11 to pass through as shown in FIG. 1. Note that while atwo-projection (e.g., 210, 212 of the first portion 102) configurationfor each top part is utilized in one embodiment as discussed above, thepresent invention can be practiced with other alternativeconfigurations. For instance, each top part may just have oneprojection, or three or more projections.

[0058] The top part 104 of the first portion 102 further has an edge 242with toothed surface 243 positioned on the first side surface 202.Additionally, the top part 104 of the first portion 102 has an edge 244with toothed surface 245 positioned on the second side surface 204.Correspondingly, the top part 154 of the second portion 152 has a groove246 positioned on the first side surface 222. A close pin 248 isreceived partially in the groove 246 on the first side surface 222,wherein the close pin 248 has a first end 250 with teeth 251complimentary to the toothed surface 243 of the edge 242 on the firstside surface 202 and a second end 252 opposite the first end 250. Thetop part 154 of the second portion 152 further has a connecting pin 254that penetrates the groove 246 through portions of the top part 154 andthe close pin 248. In this embodiment, the close pin 248 is pivotallyattached to the top part 154 of the second portion 152 through theconnecting pin 254 so that when the second end 252 of the close pin 248is pushed in a first direction, say, toward to the first side surface222, the first end 250 of the close pin 248 moves in an opposite seconddirection, i.e., away from the first side surface 222, to allow theteeth 251 to disengage the toothed surface 243. Optionally, an elasticmember 254 a such as a spring can be utilized to facilitate the couplingof the close pin 248 with the top part 154 of the second portion 152. Inone embodiment, the elastic member 254 a is attached to the close pin248 at one end and received in a recess 246 a in the groove 246 at theother end.

[0059] Additionally, the top part 154 of the second portion 152 can havea groove 256 positioned on the second side surface 224. A close pin 258is received partially in the groove 256 on the second side surface 224,wherein the close pin 258 has a first end 260 with teeth 261complimentary to the toothed surface 245 of the edge 244 on the secondside surface 222 and a second end 262 opposite the first end 260. Thetop part 154 of the second portion 152 further has a connecting pin 264that penetrates the groove 256 through portions of the top part 154 andthe close pin 258. In this embodiment, the close pin 258 is pivotallyattached to the top part of the second portion through the connectingpin 264 so that when the second end 262 of the close pin 258 is pushedin a first direction, say, toward to the second side surface 224, thefirst end 260 of the close pin 258 moves in an opposite seconddirection, i.e., away from the second side surface 224, to allow theteeth 261 to disengage the toothed surface 245. Optionally, an elasticmember 264 a such as a spring can be utilized to facilitate the couplingof the close pin 258 with the top part 154 of the second portion 152. Inone embodiment, the elastic member 264 a is attached to the close pin258 at one end and received in a recess 256 a in the groove 256 at theother end.

[0060] Referring now to FIGS. 1 and 5, a position pin 270 pivotallycouples the bottom parts 108, 158 of the first and second portions 102,152 together. In one embodiment, the bottom part 108 of the firstportion 102 has a first leg 272 and a second leg 274 defining a spacetherebetween. Correspondingly, the bottom part 158 of the second portion152 has a first leg 282 and a second leg 284 defining a spacetherebetween. The first leg 282 and the second leg 284 of the bottompart 158 of the second portion 152 are complimentary, position wise andsize wise, to the first leg 272 and the second leg 274 of the bottompart 108 of the first portion 102 to allow the second leg 284 of thebottom part 158 of the second portion 152 to be received in the spacebetween the first leg 272 and the second leg 274 of the bottom part 108of the first portion 102, and the first leg 272 of the bottom part 108of the first portion 102 to be received in the space between the firstleg 282 and the second leg 284 of the bottom part 158 of the secondportion 152. Other coupling mechanisms can also be utilized. Forexample, each bottom part may just have one leg and be coupled togetherthrough a position pin.

[0061] In operation, as shown in FIG. 6, the holding device 100 isopened to receive the mold assembly 11. Then the first portion 102 andthe second portion 152 of the holding device 100 are closed so that themolding assembly 11 is received in the housing 120 with the tail 41 topass through the opening 240 as shown in FIGS. 1 and 4. Close pins 248,258 engage with the toothed surfaces 243, 245, respectively, to keep themolding assembly 11 properly positioned in the holding device 100. Inthis configuration, the port 42 is in fluid communication with themolding cavity 16 and the ambient air. In this regard, it is noted thatthe plug 44 should be sized not to completely block the fluidcommunication between the port 42 and the molding cavity 16. The bore114 of the top part 104 of the first portion 102 is sized to allow afluid injecting means such as an injecting or filling needle 8 to passthrough to reach the mold assembly 11. Likewise, the bore 164 of the toppart 154 of the second portion 152 is sized to allow a fluid injectingmeans such as the filling needle 8 to pass through to reach the moldassembly. In the configuration shown in FIGS. 1 and 2, the fillingneedle 8, which may further be in fluid communication with a supply offluid lens forming material (not shown), passes through the bore 164 ofthe top part 154 of the second portion 152, reaches the mold assembly11, pierces through the sleeve 50 at a position along the encircledportion 36 of the strip 20 so as to establish a fluid communication withthe molding cavity 16 through the channel 38, and then fills the moldingcavity 16 with the fluid lens-forming material. Because the encircledportion 36 of the strip 20 protrudes away from the outer surface 30 ofthe strip 20, it provides an easier target for the filling needle 8 topenetrate than what prior art can offer. Once a proper amount of thefluid lens-forming material is introduced into the cavity 16, thefilling needle 8 withdraws from the cavity 16 and the sleeve 50. Theelastomeric character of the sleeve 50 insures that no unnecessary airis introduced into and no fluid lens-forming material escapes from thecavity 16. The fluid lens-forming material is then cured and hardened.Note that to speed up the filling process, multiple filling needles maybe utilized through the bores 114, 164.

[0062] As one skilled in the art will appreciate, Turing can beaccomplished in a number of ways. For example, the curing method of thepresent invention involves exposing the fluid lens-forming materialfirst a microwave radiation for a desired time and then to anultraviolet (“UV”) light for a desired time. Alternatively, afterexposing the fluid lens-forming material to UV light, the fluidlens-forming material is then heated for a predetermined time, such asin an infra-red (“IR”) oven. The second heating step solidifies thefluid lens-forming material to form the hardened lens if notsufficiently cured in the UV step.

[0063] During the curing process, the volume of the fluid lens-formingmaterial shrinks approximately ten to fifteen percent. To compensate theshrinkage, the molds 12, 14 may slide axially along the sleeve 50. As aresult, the stresses within the lens are reduced and thus a better lensis produced. The molds in the prior art T-gasket, in contrast, remainstationary, regardless of the stresses from shrinkage, while the moldsin the prior-art tape arrangement drag the tape or strip to make itcrumple or wrinkle. The venting to the ambient air can be accomplishedthrough the port 42.

[0064] Thereafter, the holding device 100 can be opened, and the moldingassembly 11 can be disassembled, for example, by simply tearing off thesleeve 50, to obtain the optical lens, which can be further processed.

[0065] During the molding process, often it needs to transport anoptical device such as a mold from one place to another place, or toposition the optical device at a desired location or position. In doingso, one must be careful not to touch the optical surface of the mold tokeep the optical surface of the mold clean so that the quality ofoptical lenses to be molded from the mold is not compromised. As usedhere referring to a mold, the term “optical surface” refers to a surfaceof the mold that has proper geometric shape and optical characteristicsand will be in direct contact with the liquid lens-forming material toproduce a desired optical lens. For example, as shown in FIG. 3, themold 12 has an optical surface 17, and the mold 14 has an opticalsurface 19. The optical surface 17 and the optical surface 19 are facingto each other defining the molding cavity 16 to produce a desiredoptical lens.

[0066] In another aspect, the present invention provides an apparatus500 for holding a mold such as mold 60 shown in FIG. 7, wherein the mold60 has an optical surface 62 and a second surface 64 opposite theoptical surface 62 and is characterized by a radius R_(m).

[0067] In one embodiment, referring generally now to FIGS. 7-10, theapparatus 500 includes a first ring 300. The first ring 300 defines anopening 302 and a ring body 304. The ring body 304 has a longitudinalaxis A₁, a first surface 310 and an opposite second surface 312, and anouter surface 306 and an interior surface 308. The outer surface 306 ischaracterized by a first radius, R₁, and the interior surface 308 ischaracterized by a second radius, R₂. Moreover, a plurality of teeth 314are formed on the first surface 310 in a circle 316 and protruding awayfrom the ring body 304 along the longitudinal axis A₁. The circle 316 ischaracterized by a radius, R_(c), which is complementary to the radiusof the mold 60, R_(m), to allow the plurality of teeth 314 to receiveand hold the mold 60.

[0068] The radii of the mold 60 and the circle 316 generally satisfy thefollowing relationship: R_(c)≧R_(m). The radii of the outer surface 306and the interior surface 308 of the ring body 304, the mold 60 and thecircle 316 generally satisfy the following relationship:R₁≧R_(c)≧R_(m)≧R₂.

[0069] Additionally, the first ring 300 has an optional step 318 formedon the first surface 310 adjacent to the plurality of teeth 314 andextending inwardly from the plurality of teeth 314 toward thelongitudinal axis A, for receiving the mold 60 and supporting the mold60 therein. The step 318 has a substantially ring-like structure and ischaracterized by a radius R_(s) that satisfies the followingrelationship: R_(c)≧R_(s)≧R₂. Note that while the step 318 providesfurther support to the mold 60 received therein, it is not necessary tohave the step 318 in the first ring 300 because the plurality of teeth314 can adequately receive and hold the mold 60. Moreover, the firstring 300 has an edge 320 formed on the ring body 304 between theinterior surface 308 of the ring body 304 and the step 318.

[0070] The plurality of teeth 314 can be formed with elastic materialssuch as plastics, metals or like such as NORYL, a plastic material soldby GE Plastics, DELRIN, a plastic material sold by Du Pont, or may beother plastic materials such as polypropylene. Each of the plurality ofteeth 314 has a width, a thickness, and a length. The width, thethickness and the length of each of the plurality of teeth 314 are inthe range of 0.1 cm to 2.0 cm, 0.01 cm to 0.5 cm, and 0.1 cm to 2.0 cm,respectively. There is no requirement for the total number of theplurality of teeth 314. In general, the number of the plurality of teeth314 is a number no smaller than 2. However, in an extreme case, theplurality of teeth 314 can be merged together to form a unified ring,which is an alternative embodiment of the present invention and thenumber of the plurality of teeth 314 is one for this alternativeembodiment. The plurality of teeth 314 can be substantially identicalto, or different from, each other. The plurality of teeth 314 can beuniformly, or non-uniformly, distributed along the circle 316. Differentparts of the first ring 300 can be made from same material, or differentmaterials. In the embodiment as shown in FIGS. 7-10, the first ring 300is manufactured by molding and made from a plastic material such asNORYL, a plastic material sold by GE Plastics, DELRIN, a plasticmaterial sold by Du Pont, or may be other plastic materials such aspolypropylene.

[0071] The apparatus 500 further includes a second ring 400. As shown inFIGS. 7-9, in one embodiment, the second ring 400 has a base 402 and aring body 408. The base 402 has a first surface 404 and an oppositesecond surface 406. The ring body 408 is formed on the first surface 404of the base 402. The ring body 408 has a longitudinal axis (A₂), a topsurface 410, an outer surface 412 and an interior surface 414. The outersurface 412 is characterized by a first radius, R′₂, and the interiorsurface 414 is characterized by a second radius, R₁₂. A plurality ofteeth 416 are formed on the top surface 410 in a circle 418 andprotruding away from the ring body 408 along the longitudinal axis A₂.The circle 418 has a radius, R′_(c), complementary to the radius of themold 60, R_(m,) to allow the plurality of teeth 416 to be capable ofreceiving and holding the mold 60. Each of the teeth 416 has a bottom420, a tip 422, and a body portion 424 formed therebetween. Moreover,each of the teeth 416 has a step 426 formed on the body portion 424inwardly toward the longitudinal axis A₂ to partially receive andsupport the mold 60. The plurality of teeth 416 and steps 426collectively receive, hold and support the mold 60. Note that while thesteps 426 provide further support to the mold 60 received therein, it isnot necessary to have the steps 426 in the second ring 400 because theplurality of teeth 416 can adequately receive and hold the mold 60.Moreover, it is not necessary for each of the plurality of the teeth 416to have a step 416. Additionally, the steps 426 can be alternativelyreplaced by a step formed in a substantially ring-like structure such asstep 318 of the first ring 300.

[0072] The plurality of teeth 416 can be formed with elastic materialssuch as plastics, metals or like such as NORYL, a plastic material soldby GE Plastics, DELRIN, a plastic material sold by Du Pont, or may beother plastic materials such as polypropylene. Each of the plurality ofteeth 416 has a width, a thickness, and a length. The width, thethickness and the length of each of the plurality of teeth 416 are inthe range of 0.1 cm to 2.0 cm, 0.01 cm to 0.5 cm, and 0.1 cm to 2.0 cm,respectively. There is no requirement for the total number of theplurality of teeth 416. In general, the number of the plurality of teeth416 is a number no smaller than 2. However, in an extreme case, theplurality of teeth 416 can be merged together to form a unified ring,which is an alternative embodiment of the present invention and thenumber of the plurality of teeth 416 is one. The plurality of teeth 416can be substantially identical to, or different from, each other. Theplurality of teeth 416 can be uniformly, or non-uniformly, distributedalong the circle 418. Different parts of the second ring 400 can be madefrom same material, or different materials. In the embodiment as shownin FIGS. 7-9, the second ring 400 is manufactured by molding and madefrom a plastic material such as NORYL, a plastic material sold by GEPlastics, DELRIN, a plastic material sold by Du Pont, or may be otherplastic materials such as polypropylene.

[0073] The apparatus 500 further has a sleeve 428 to cooperate with thesecond ring 400. In one embodiment and as shown in FIGS. 7-9, the sleeve428 has an interior surface 430 and an opposed outer surface 432, afirst end 431 and a second end 433, a longitudinal axis and a diametercomplementary to the ring body 408 of the second ring 400 to allow thesleeve 428 to be received on the first surface 404 of the base 402 suchthat the sleeve 428 and the ring body 408 are co-axial.

[0074] Various coupling mechanisms can be utilized to rotatably couplesleeve 428 to the ring body 408. In one embodiment as shown in FIG. 8,the ring body 408 has a groove 434 formed on the outer surface 412around the longitudinal axis, and the sleeve 428 has at least one hole436 formed between the outer surface 412 and the interior surface 414.At least one locking pin 440 is received in the hole 436 of the sleeve428 and the groove 434 of the ring body 408 to couple the ring body 408and the sleeve 428 together. Because the groove 434 is formed on theouter surface 412 around the longitudinal axis, the locking pin 440 canmove around the longitudinal axis in the groove 434 when the sleeve 428is rotated.

[0075] The sleeve 428 further has marks 438 indicating angularpositions. In one embodiment as shown in FIG. 7, marks 438 arepositioned on the first end 431 and the outer surface 432 of the sleeve428. Alternatively, marks 438 can be positioned on the first end 431 orthe outer surface 432 of the sleeve 428, respectively. Cooperating witha mark 338 positioned on the mold 60, marks 438 can be utilized toorient the mold 60 at a proper angular position relative to another mold(not shown) so that the molds will be positioned properly to have adesired relative orientation.

[0076] In operation, referring now to FIGS. 7 and 8, one can use thefirst ring 300 to pick up the mold 60 with the plurality of teeth 314towards the second surface 64 of the mold 60 to receive and hold themold 60 so that the optical surface 62 of the mold 60 is facing awayfrom the first ring 300. By doing so, the risk of the optical surface 62being accidentally touched by human hands is greatly reduced. Moreover,it is easy to handle, process or transport the mold 60 by handling thefirst ring 300 when the mold 60 is received in the first ring 300. Forexample, once the mold 60 is received and supported in the first ring300, one can access to the optical surface 62 to apply a coating thereinthrough the opening 302.

[0077] Additionally, one can take the combination of the mold 60 and thefirst ring 300 and direct the mold 60 so that the optical surface 62 ofthe mold 60 faces the second ring 400. Care should be taken to ensurethat the first ring 300 and the second ring 400 are positioned properlyand co-axial. The first ring 300 can be moved and pushed towards thesecond ring 400 so that the second ring 400 receives and holds the mold60 with the optical surface 62 of the mold 60 facing towards to thefirst surface 404 of the base 402 of the second ring 400. In thisconfiguration, the optical surface 62 is isolated from the outside bythe base 402, the sleeve 428 and the second surface 64 of the mold 60and therefore is protected from dirt, accidental touch or damage. Themold 60 can then be stored and/or transported with the second ring 400for further processing. For example, the mold 60 can be transported tothe holding device 100 for assembly. The first ring 300 can be removedfrom the mold 60. Alternatively, the first ring 300 can stay with themold 60.

[0078] The mold 60 as shown in FIGS. 7 and 9 has a concave opticalsurface 62. The mold 60 can be a front mold or a back mold. Thus, themold 60 may alternatively have a convex optical surface. The apparatus500 can still be utilized to hold, transfer and protect the mold withthe convex optical surface as discussed above. In this case, one canfirst use the second ring 400 (as a first ring) to pick up the mold withthe convex optical surface facing towards to the first surface 404 ofthe base 402 of the second ring 400. Then the first ring 300 can be used(as a second ring) to pick up and hold the mold from the second ring400. The mold can then be held, processed and/or transported.

[0079] From the above discussion, the apparatus 500 can be considered asan optical device or mold carrier. Note that while the apparatus 500 isdescribed to utilize the first ring 300 and the second ring 400, each ofthe first ring 300 and the second ring 400 can be used individually.

[0080] Although the present invention has been described with referenceto specific details of certain embodiments thereof, it is not intendedthat such details should be regarded as limitations upon the scope ofthe invention except as and to the extent that they are included in theaccompanying claims.

1-47. (Cancelled)
 48. An apparatus for holding a mold, wherein the moldhas and optical surface and a second surface opposite the opticalsurface and is characterized by a radius R_(m), comprising: a. a firstring defining an opening, the first ring comprising: i. a ring had alongitudinal axis, a first surface and an opposite second surface, andan outer surface and an interior surface, wherein the outer surface ischaracterized by a first radius, R₁, and the interior surface ischaracterized by a second radius, R₂: and ii. a plurality of teethformed on the first surface in a circle and protruding away from thering body along the longitudinal axis, wherein the circle has a radius,R_(c), complementary to the radius of the mold R to allow the pluralityof teeth to receive and hold the mold.
 49. The apparatus of claim 48,wherein the radii of the mold and the circle satisfy the followingrelationship: R_(c)≧R_(m).
 50. The apparatus of claim 48, wherein theradii of the outer surface and the interior surface of the ring body,mold and the circle satisfy the following relationship:R₁≧R_(c)≧R_(m)≧R₂.
 51. The apparatus of claim 48, wherein the first ringfurther has a step formed on the first surface adjacent to the pluralityof teeth and extending inwardly form the plurality of teeth forreceiving the mold.
 52. The apparatus of claim 51, wherein the step hasa substantially ring-like structure and characterized by a radius R_(s)that satisfies the following relationship: R_(c)≧R_(s)≧R₂
 53. Theapparatus of claim 52, wherein the first ring further has an edge formedon the ring body between the interior surface of the ring body and thestep.
 54. The apparatus of claim 48, wherein the plurality of teeth areformed with a material comprising an elastic material.
 55. The apparatusof claim 54, wherein the elastic material includes plastics.
 56. Theapparatus of claim 48, further comprising: b. a base having a firstsurface and an opposite second surface; i. a ring body formed on thefirst surface of the base, the ring body having a longitudinal axis(A₂), a top surface, an outer surface and an interior surface, whereinthe outer surface is characterized by a first radius, R′₁, and theinterior surface is characterized by a second radius, R′2; and iii. aplurality of teeth formed on the top surface in a circle and protrudingaway from the ring body along the longitudinal axis, wherein the circlehas a radius, R′_(c), complementary to the radius of the mold R_(m) toallow the plurality of teeth to receive and hold the mold.
 57. Theapparatus of claim 56, wherein each of the teeth had a bottom, a tip,and a body portion formed therebetween, and a step formed on the bodyportion inwardly toward the longitudinal axis to partially receive andsupport the mold.
 58. The apparatus of claim 56, further comprising asleeve, wherein the sleeve has an interior surface and an opposed outersurface, a first end and a second end, a longitudinal axis and adiameter complementary to the ring body of the second ring to allow thesleeve to be received on the first surface of the base such that thesleeve and the ring body are co-axial.
 59. The apparatus of claim 58,wherein the sleeve is rotatably coupled to the ring body.
 60. Theapparatus of claim 59, wherein the ring body has a groove formed on theouter surface around the longitudinal axis, and the sleeve has at leastone hole formed between the outer surface and the interior surface,further comprising at least one locking pin that is received in the holeof the sleeve and the groove of the ring body to couple the ring bodyand the sleeve together.
 61. The apparatus of claim 60, wherein thesleeve further has marks indicating angular position positioned on thefirst end of the sleeve.
 62. An apparatus for holding a mold, whereinthe mold has an optical surface and a second surface opposite theoptical surface and is characterized by a radius R_(m), comprising: a. afirst ring defining an opening, the first ring comprising i. a ring bodyhas a longitudinal axis, a first surface and an opposite second surface,and an outer surface and an interior surface, wherein the outer surfaceis characterized by a first radius, R₁, and the interior surface ischaracterized by a second radius, R₂; and ii. a plurality of teethformed on the first surface in a circle and protruding away from thering body along the longitudinal axis, wherein the circle had a radiusR_(c), complementary to the radius of the mold, R_(m), to allow theplurality of teeth to receive and hold the mold; and b a second ringcomprising i. a base having a first surface 404 and an opposite secondsurface; ii. a ring body formed on the first surface of the base, thering body having a longitudinal axis (A₂), a top surface, an outersurface and in interior surface, wherein the outer surface ischaracterized by a first radius R′₁, and the interior surface ischaracterized by a second radius, R′₂; and iii. a plurality of teethformed on the top surface in a circle and protruding away from the ringbody along the longitudinal axis, wherein the circle has a radius,R′_(c), complementary to the radius of the mold R_(m) to allow theplurality of teeth to receive and hold the mold. 63-65. (Cancelled) 66.An apparatus for holding a mold, wherein the mold has an optical surfaceand a second surface opposite the optical surface and is characterizedby a radius R_(m), comprising: a. a first ring that has a longitudinalaxis and a plurality of teeth formed in a circle, wherein the circle hasa radius, R_(c), complementary to the radius of the mold, R_(m); b.means for picking up the mold so that the optical surface of the mold isfacing away from the first ring; c. a second ring that has alongitudinal axis and a plurality of teeth formed in a circle, whereinthe circle has a radius, R′_(c), complementary to the radius of themold, R_(m); d. means for directing the mold so that the optical surfaceof the mold is facing the second ring and the first ring and the secondring are co-axial; e. means for pushing the first ring towards thesecond ring so that the second ring receives and holds the mold with theoptical surface of the mold facing towards to the second ring; and f.means for removing the first ring from the mold.
 67. The apparatus ofclaim 66, further comprising means for rotating the second ring so as toposition the mold at a desired orientation.